"Hi Caitlin," the message said, addressing the company's controller, Caitlin McLaughlin. "Are you available to process an outgoing payment today? Let me know and I will send the payment details as soon as I receive it from the consultant shortly; I am traveling and this is urgent."

The only mistake was that the sender's email address spelled GreatHorn with two Rs instead of one, but that would have required eagle eyes to catch.

In addition, some email clients would only show the display name, not the actual email address, said Yoel Alvarez, IT security engineer at Philadelphia-based Hersha Hospitality Management.

"To the untrained eye, this is going to look like a legitimate email," he said. "It bypasses any form of security."

Trained users might also be put on alert by the urgency of the email and the part about the executive traveling, and might delay the transaction until they received definite confirmation from the CEO by contacting him by phone or text on a number that they already had for him.

But what if the email simply asked her something completely innocuous? Scammers will ask simple questions, questions that any co-worker or customer might ask, in order to expand their knowledge of the company, get a feel for email style, and develop relationships with staff.

These communications may also take place via social media channels, web forms, or even phone calls, said Kevin San Diego, vice president of product management at Cloudmark, which offers a spearphishing detection tool.

Traditional security email gateways or spam filters don't help when it to comes to spearphishing, he said.

"These attacks are highly targeted, with a single message in the email campaign, uniquely crafted for that particular recipient," he said.

And the messages can be very innocuous, with very simple requests that pose no risks to the company at all.

Scammers will also send out fake marketing emails in order to trigger replies from vacation autoresponders -- not only does this give them the employee's email signature, but it also tells them that the employee is on vacation and when they will be back.

The scammers can then work their way up to asking for the wire transfer, the W2 records or other proprietary data.

But there are some tell-tale signs, he added, that may not be readily apparent to the recipient.

Within 20 seconds, we recognized that it was likely an impersonation of our domain name.

"We look at the IP address of the sending domain, the age of the domain, the DNS servers that are being used, all those elements," he said.

The average cost of a spear phishing attack is $1.6 million, according to a survey released earlier this year by security firm Cloudmark and research firm Vanson Bourne, and 73 percent of respondents said that spearphishing was a significant threat.

Cyber resilience will be particularly important as Australian organisations face increased pressure to quickly detect, respond to, and manage the repercussions of breaches in the wake of 2018’s Notifiable Data Breaches (NDB) scheme.

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